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❑6.6L DURAMAX®Diesel With Engine Oil Life
System Only: Check oil life system. If engine
oil and filter are changed, reset system.
See “Engine Oil (DURAMAX
®/Isuzu Diesel)”
in the Index.(2) (9)
❑Chassis lubrication service (or every 6 months,
whichever occurs first).(11)
❑Check fluid levels (or every 3 months,
whichever occurs first).(1) (5)
❑Gasoline Engine: Inspect engine air cleaner
filter. If necessary, replace the filter. If vehicle
is driven in dusty/dirty conditions, inspect
filter at every engine oil change. SeeEngine
Air Cleaner/Filter on page 280for more
information.
❑Diesel Engine: Inspect engine air cleaner filter
change indicator. If necessary, replace the
filter. If vehicle is driven in dusty/dirty conditions,
inspect filter change indicator at every engine
oil change. SeeEngine Air Cleaner/Filter
on page 280for more information.
❑DURAMAX
®/Isuzu Diesel Only: Replace fuel
filter (or every 750 hours of engine operation,
whichever occurs first).
❑Steering system service.(12)❑Front and rear suspension service.(13)
❑Spring-to-axle U-bolts and shackle bolts
service.(15)
❑Exhaust system service (or every 6 months,
whichever occurs first).(2) (3) (16)
❑Wheels and tires service.(14)
❑Hydraulic brake service (or every 6 months,
whichever occurs first).(6) (36)
❑Parking brake service (or every 6 months,
whichever occurs first).(21)
❑Air brake service (or every 6 months, whichever
occurs first).(32)
❑Air brake automatic slack adjuster service (or
every 500 hours, whichever occurs first).(33)
❑Check air brake relay valve operation and check
for leaks (or every month, or every 300 hours,
whichever occurs first).
❑Clean air brake application valve (or every
3 months, or every 300 hours, whichever
occurs first). Lubricate linkage.
❑Air brake chamber service (or every 2 months,
whichever occurs first).(34)
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❑Fuel tank, fuel cap and fuel lines service
(or every 72 months, whichever occurs
first).(2) (26) †
❑Exhaust Gas Recirculation (EGR) system
inspection (if equipped) (or every 72 months,
whichever occurs first).(2) (27)
❑Thermostatically controlled engine cooling
fan service.(3) (19)
❑Shields and underhood insulation
service.(3) (4) (20)
❑Gasoline Engine: Air compressor remote
mounted air filter dry element pleated paper
air strainer service (or every 6 months or
every 1800 hours, whichever occurs first).
82,500 Miles (132 000 km)
❑Gasoline Engine Only: Check engine oil life
system. If engine oil and filter are changed,
reset system. See “Engine Oil (Gasoline
Engine)” in the Index.(2) (8)
❑Check fluid levels (or every 3 months,
whichever occurs first).(1) (5)❑Chassis lubrication service (or every 6 months,
whichever occurs first).(11)
❑Wheels and tires service.(14)
❑Hydraulic brake service (or every 6 months,
whichever occurs first).(6) (36)
❑Parking brake service (or every 6 months,
whichever occurs first).(21)
❑Air brake service (or every 6 months, whichever
occurs first).(32)
❑Air brake automatic slack adjuster service (or
every 500 hours, whichever occurs first).(33)
❑Check air brake relay valve operation and check
for leaks (or every month, or every 300 hours,
whichever occurs first).
❑Clean air brake application valve (or every
3 months, or every 300 hours, whichever
occurs first). Lubricate linkage.
❑Air brake chamber service (or every 2 months,
whichever occurs first).(34)
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84,000 Miles (140 000 km)
❑Isuzu 6H Diesel Without Engine Oil Life System
Only: Change engine oil and filter (or every
12 months, or every 600 hours of engine
operation, whichever occurs first).(2)
❑Isuzu 6H Diesel With Engine Oil Life System
Only: Check oil life system (or every 12 months,
or every 600 hours of engine operation,
whichever occurs first). If engine oil and filter
are changed, reset system. See “Engine Oil
(DURAMAX
®/Isuzu Diesel)” in the Index.(2) (7)
90,000 Miles (144 000 km)
❑Gasoline Engine Only: Check engine oil life
system. If engine oil and filter are changed,
reset system. See “Engine Oil (Gasoline
Engine)” in the Index.(2) (8)
❑6.6L DURAMAX
®Diesel Without Engine Oil
Life System Only: Change engine oil and
filter (or every 12 months, or every 750 hours
of engine operation, whichever occurs first).(2)
❑6.6L DURAMAX
®Diesel With Engine Oil
Life System Only: Check oil life system.
If engine oil and filter are changed, reset
system. See “Engine Oil (DURAMAX
®/Isuzu
Diesel)” in the Index.(2) (9)❑Check fluid levels (or every 3 months,
whichever occurs first).(1) (5)
❑Gasoline Engine: Replace engine air cleaner
filter. SeeEngine Air Cleaner/Filter on
page 280for more information.
❑Diesel Engine: Inspect engine air cleaner filter
change indicator. If necessary, replace the
filter. If vehicle is driven in dusty/dirty conditions,
inspect filter change indicator at every engine
oil change. SeeEngine Air Cleaner/Filter
on page 280for more information.
❑DURAMAX
®/Isuzu Diesel Only: Replace fuel
filter (or every 750 hours of engine operation,
whichever occurs first).
❑Chassis lubrication service (or every 6 months,
whichever occurs first).(11)
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❑Cooling system service. Clean the cooling
system filler cap with clean water, clean
the core, pressure test the cap and the
system for proper pressure capability, and
inspect condition of cooling and heater
hoses and clamps. Replace hoses if cracked,
swollen, or damaged.
❑Replace fuel filter(s) (or every 12 months,
whichever occurs first).(2)
❑Steering system service.(12)
❑Front and rear suspension service.(13)
❑Spring-to-axle U-bolts and shackle bolts
service.(15)
❑Exhaust system service (or every 6 months,
whichever occurs first).(2) (3) (16)
❑Inspect door hinge pins and bushings and
replace as necessary.
❑Wheel bearing (grease type) service (and
whenever hubs are removed).(22) (36)
❑Wheels and tires service.(14)
❑Hydraulic brake service (or every 6 months,
whichever occurs first).(6) (36)
❑Parking brake service (or every 6 months,
whichever occurs first).(21)❑Air brake service (or every 6 months, whichever
occurs first).(32)
❑Air brake automatic slack adjuster service (or
every 500 hours, whichever occurs first).(33)
❑Check air brake relay valve operation and check
for leaks (or every month, or every 300 hours,
whichever occurs first).
❑Clean air brake application valve (or every
3 months, or every 300 hours, whichever
occurs first). Lubricate linkage.
❑Air brake chamber service (or every 2 months,
whichever occurs first).(34)
❑Air brake system valve service (or every
3 months, or every 900 hours, whichever
occurs first).(37)
❑C600, C700, and C800 Gasoline Engines
Only: Engine drive belts service (or every
12 months, whichever occurs first).(17)
❑Thermostatically controlled engine cooling
fan service.(3) (19)
❑Shields and underhood insulation
service.(3) (4) (20)
❑Rear axle air shift motor service.(10)
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❑Air intake system service (or every 24 months,
whichever occurs first).(3) (4) (23)
❑Evaporative Control System service,
if equipped, (or every 24 months,
whichever occurs first).(2) (24) †
❑Gasoline Engine: Air compressor remote
mounted air filter dry element pleated paper
air strainer service (or every 6 months or
every 1800 hours, whichever occurs first).
96,000 Miles (152 000 km)
❑Isuzu 6H Diesel Without Engine Oil Life System
Only: Change engine oil and filter (or every
12 months, or every 600 hours of engine
operation, whichever occurs first).(2)
❑Isuzu 6H Diesel With Engine Oil Life System
Only: Check oil life system (or every 12 months,
or every 600 hours of engine operation,
whichever occurs first). If engine oil and filter
are changed, reset system. See “Engine Oil
(DURAMAX
®/Isuzu Diesel)” in the Index.(2) (7)
❑Lubricate U-joints (or every 6 months,
whichever occurs first).
97,500 Miles (156 000 km)
❑Gasoline Engine Only: Check engine oil life
system. If engine oil and filter are changed,
reset system. See “Engine Oil (Gasoline
Engine)” in the Index.(2) (8)
❑Check fluid levels (or every 3 months,
whichever occurs first).(1) (5)
❑Chassis lubrication service (or every 6 months,
whichever occurs first).(11)
❑Wheels and tires service.(14)
❑Hydraulic brake service (or every 6 months,
whichever occurs first).(6) (36)
❑Parking brake service (or every 6 months,
whichever occurs first).(21)
❑Air brake service (or every 6 months,
whichever occurs first).(32)
❑Air brake automatic slack adjuster service (or
every 500 hours, whichever occurs first).(33)
❑Check air brake relay valve operation and check
for leaks (or every month, or every 300 hours,
whichever occurs first).
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❑Clean air brake application valve (or every
3 months, or every 300 hours, whichever
occurs first). Lubricate linkage.
❑Air brake chamber service (or every 2 months,
whichever occurs first).(34)
100,000 Miles (160 000 km)
❑Diesel Only: Inspect engine drive belt;
replace as necessary.
❑Gasoline Engine Only (Vehicles with
GVW of 16,000 lbs or less): Spark plug
service.(2) (25)
❑Change power steering fluid (or every
36 months, whichever occurs first).(12)
❑Replace power steering reservoir filter element
(or every 24 months, whichever occurs first).
❑Wheel bearing (oil type) service (and whenever
hubs are removed).(22) (36)
❑Except four-wheel drive: Front axle service.(31)
❑Four-wheel drive only: Front axle service.(30)
❑Four-wheel drive only: Transfer case
service.(30)
❑Rear axle service — Eaton
®, Rockwell®,
Spicer®axles (or every 12 months, whichever
occurs first).(30)❑Exhaust brake service, if equipped. Check for
excessive spindle free play and smooth
operation. Lubricate ball joint cap.
❑Inspect air compressor discharge port (or every
6 months or every 1,800 hours, whichever
occurs first).
❑Manual transmission (ZF 6-speed only) fluid
replacement (or every 48 months, whichever
occurs first).
❑Trailer brake hand control valve service (or every
12 months, or every 3,600 hours, whichever
occurs first).(35)
120,000 Miles (192 000 km)
❑C600, C700, and C800 Gasoline Engines Only:
Replace engine drive belts.
❑C400 and C500 Gasoline Engines Only: Engine
drive belts service (or every 12 months,
whichever occurs first).(17)
150,000 Miles (240 000 km)
❑Cooling system service (or every 60 months
since last service, whichever occurs
first).(2) (29)
❑Diesel Engine Only: Inspect engine drive belt;
replace as necessary.
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200,000 Miles (320 000 km)
❑Rear axle service — Eaton®, Rockwell®,
Spicer®axles (or every 12 months,
whichever occurs first).(30)
❑Remove, disassemble, clean, and inspect the
air brake trailer supply valve (or every 2 years,
or every 7,200 hours, whichever occurs first).
❑Diesel Engine Only: Inspect engine drive belt;
replace as necessary.
250,000 Miles (400 000 km)
❑Four-wheel drive only: Front axle service.(30)
❑Four-wheel drive only: Transfer case
service.(30)
❑Manual transmission (except ZF 6-speed)
fluid replacement (or every 60 months,
whichever occurs first).
300,000 Miles (480 000 km)
❑Rear axle service — Eaton®, Rockwell®,
Spicer®axles (or every 12 months,
whichever occurs first).(30)
❑Remove, disassemble, clean, and inspect
the air brake air dryer (or every 3 years,
or 10,800 hours, whichever occurs first).
Replace desiccant.
Footnotes
† = The U.S. Environmental Protection Agency
or the California Air Resources Board has
determined that the failure to perform this
maintenance item will not nullify the emission
warranty or limit recall liability prior to the
completion of the vehicle’s useful life. We,
however, urge that all recommended maintenance
services be performed at the indicated intervals
and the maintenance be recorded.
(1)= If your vehicle has an Allison Transmission
®,
your GM owner manual is supplemented by an
Allison Transmission
®Operator’s Manual. Always
refer to these manuals for related maintenance
services.
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(2)= An Emission Control Service.
(3)= A Noise Emission Control Device.
(4)= Applies to vehicles sold in the United States
and is recommended for vehicles sold in Canada.
(5)= Check fluid level in brake master cylinder,
power steering pump, front and rear axles,
transmission, and hydraulic spring parking brake
pump (if equipped). A low fluid level in the
brake master cylinder can indicate worn brake
linings and should be checked accordingly.
(6)= Inspect brake lines and hoses for proper
hook-up, binding, leaks, cracks, chafing, etc.
Inspect disc brake pads for wear and rotors for
surface condition. Inspect caliper assemblies.
Check brake pedal for excessive free play or
travel (or every 6 months, whichever occurs first)
and have serviced if needed. Check brakes
more often if driving habits and conditions result
in frequent braking.(7)= This vehicle has the Engine Oil Life System.
This system will show you when to change the
engine oil and filter — usually between 3,000 miles
(5 000 km) and 12,000 miles (20 000 km) since
your last oil change. Under severe conditions,
the indicator may come on before 3,000 miles
(5 000 km). Never drive your 7.8L diesel engine
vehicle more than 12,000 miles (20 000 km),
or 12 months, or 600 engine hours, without an
oil and filter change.
Remember to reset the Engine Oil Life System
whenever the oil is changed. For more information,
seeEngine Oil Life System (Gasoline Engine)
on page 276orEngine Oil Life System
(DURAMAX
®Diesel) on page 278orEngine
Oil Life System (Caterpillar®Diesel Engine)
on page 279.
384